Spraying adhesive-coated material



arch W, 1937. BRAMSEN 2,U73,7'79

SPRAYING ADHESIVE COATED MATERIAL Filed NOV. 27, 1935 2 Sheets-Sheet larch 16, 1937. s. BRAMSEN 2,073,779

SPRAYING ADHESIVE COATED MATERIAL Filed Nov. 27, 1955 2 Sheets-Sheet 2M/YATER/AL \jzfe'nd 576177126922 jade 72167;

Patented Mar. 16, I?

[UNITED STATES PATENT I orrlcs Svend Bramsen, Chicago, Ill., assignor'toBinks Manufacturing Company, Chicago, 111., a. corporation of DelawareApplication November 21, 1935, Serial No. 51,163'

' 15 Claims.

In its general objects, my invention relates to means for interminglinga liquid with a comminuted material in definite proportions andthereafter conjointly spraying the resulting mix-' ture, and moreparticularly to av spraying installation of this class forsurface-coating porous material with an adhesive or other binder.

When ground cork, asbestos, shredded paper or the like are used as a.filling between the inner l0 and outer walls in parts of a building, orin the hollow walls of an automobile, for either sounddeadening orheat-insulating purposes, it is important that the particles of suchmaterials shall not be free to be packed down by jarring, or grad- 15ually packed down merely by their own weight.

Consequently, it is already customary to use an adhesive liquid forbinding the solid particles of material to one another and for alsobinding the walls to adjacent material particles, so as to pre- 20 venta relative displacement of the material particles after the filling iscompleted.

According to one of the heretofore customary procedures, this has beendone by projecting separately formed sprays of the comminutedmaterialand of the adhesive liquid with the aid of pneumatic sprayappliances in such a manner that the material and liquid willintermingle after their discharge from the said appliances and beforereaching the space which is to be filled. With this procedure, anundesirably large proportion of the adhesive liquid is projected betweenthe particles of the sprayed solid material, and the coating of theparticles is far from uniform, so that an excessive amount of theadhesive or other binder is required for insuring even a fairly stablefilling.

As an alternative procedure, it has also been proposed to feed thecomminuted material and the binder separately into a spray appliance of40 the general class of a spray gun, so as to mix the said material withthe binder while within the gun. In practice, this has the objectionthat the usually irregular shapes and sizes of the solid materialparticles will prevent a uniform mixing of these particles with thebinder, so that some of the material will issue without aving anadhesive coating on it, while arr/e cessive adhesive coating on otherparticles of the solid material will cause these to clog the gun.Mgreover, neither of the just described procedures is economical for usewith any gritty material (as for example, scraps of asbestoswhen thespraying has to be done at some distance from the material supply tank)because a dry material of this 55 nature will grind through the pipingand likewise will cause undue wear on the material passages of a spraygun.

When the sound-deadening material is absorbentas for example, withground corkan undue absorption of the liquid binder by the cork whilebeing mixed with the latter within a spray gun will fill an excessiveproportion of the air spaces within the cork; thereby greatlyreducing'the sound-deadening and heat-insulating properties of thatmaterial, and also requiring an excessive proportion of the binder. Toovercome these objections, it has heretofore been proposed to waterproofthe particles of cork, shredded paper or the like first, but this inturn increases the expense undesirably.

My present invention aims to provide an apparatus which will eifectivelyapply a surfacecoating of the adhesive or other binder to the solidmaterial while still leaving the internal air spaces of the materialfilled with air, thereby also causing this adhesive coating to act afterthe manner of a lubricant for enabling the material (even if this isasbestos or other porous mineral) to travel readily through ducts ofconsiderable length without causing undue wear.

Furthermore, my invention aims to provide an apparatus which will insurean adequate surface-coating of the solid material before the start ofthe spraying operation, so as to maintain a predetermined proportioningof the adhesive or binder to the solid material throughout the sprayingoperation; which will automatically halt the feeding and the mixing ofboth the solid material and the binder whenever the spraying isinterrupted; and which will permit an easy and speedy cleaning of themixer, the pipe lines and the spray guns at the close of the days orhalfdays spraying time.

Morever, my invention aims to provide an apparatus of the above recitedcharacteristics which can readily be adjusted both as to theproportioning of the binding liquid to the material; and for maintaininga predetermined quantity of liquid in the mixer; which will preventatmospheric air from reaching either the material or the liquid; and inwhich compressed air will propel the surface-coated material throu h themixer and the discharge duct and through the associated spray guns.

Illustrative of the manner in which I accomplish the above recitedobjects, as well as more detailed objects, i

Fig. 1 is a somewhat diagrammatic elevation of a spray apparatusembodying my invention, showing the discharge duct as connected to asingle spray gun, and showing the use of separate motors for measuringthe material and the liquid binder into a mixer, and for agitating theresulting mixture within the mixer.

Fig. 2 is an elevation similar to a portion of Fig. 1, showing the useof a single motor connected directly to the agitator, and connected byindependent variable speed drives to the two feed mechanisms. l0

gun particularly suitable for use in spraying adhesive-coated material,the gun being equipped with a switch for connection to the correspondingcircuit in Fig. 1 or Fig. 2.

In Fig. 1, the frame-work F supports both a material tank T and a liquidtank L at a considerable elevation above the casing M of a mixer, eachof these tanks having a cover C sealed to it and having its upperportion connected to a pipe A to which compressed air is suppliedthrough a pressure-regulator R. The material tank T has its lowerportion T formed for housing a metering dispenser I which measures thematerial supplied through a material pipe P into the mixer 5 casing M,this dispenser being driven by an electric motor 2. A second meteringdispenser 3 is disposed in a liquid pipe 5 leading from the bottom ofthe liquiding tank L into the upper portion of the mixer; this dispenserbeing driven by a second electric motor 4.

The liquid pipe 5 desirably has its lower portion extending horizontallyinto, the mixer casing M above the rotating paddles 6 which co-operatewith the stationary paddles I for agitating the contents of the mixer.These paddles are fast upon an upright shaft 8 rotated by an electricmotor 9, each of the said three motors being of an adjustable speed typeand the three motors being connected in multiple to a two-wire circuitleading from terminals II.

This circuit is arranged so that it is open when my spraying apparatusis idle, and so that it can be closed either for a predetermined shorttime interval by a manually started time switch i 2 or by acircuit-closer l3 associated with a spray-gun G connected by a hose H tothe bottom discharge outlet of the material tank M.

The time switch may be of a commercial type in which a circuit betweentwo terminals is closed by digitally pressing a button B, and in whicheither a clockwork or a synchronous motor automatically opens thecircuit after a predetermined time interval.

In starting my apparatus with no material or liquid in the mixer casing,the user first presses the switch button B, thereby causing all three ofthe motors, so as to actuate both the measured feeding of material i 5from the material tank and liquid L from the liquid tank to the mixer,

and also to rotate the agitator so that the material particles will rubupon each other to distribute the liquid coating upon them. When theoperator is informed by the click of the time switch during its openingof the switch (or visually by seeing the button B snap out again) thatthe agitator has effected the needed minimum filling and stirring of themixer, he operates the spray gun G by retracting the usual gun-actuatingmember 9, thus closing the current-supply circuit so as to start allthree of the said motors again.

Whenever the user thereafter operates the gun, the two meteringdispensers l and 3 feed material and liquid respectively, at the ratesfor which the speeds of the corresponding motors are Fig. 3 is anenlarged perspective view of a spray adjusted, to the mixer M and theagitator 8 likewise operates (at the rate for which the motor 0 wasadjusted) for distributing the liquid onthe granules of material beforethey are forced through the hose H to the spray gun. Thus, the timedswitch only needs to be actuated at the beginning of each sprayingperiod, and its time adjustment can be such (as for example a quarter ofa minute) that the adhesive is not yet adequately distributed! over theupper layers of granules in the mixer, since these will be furtheragitated before their discharge for spreading the adhesive over them.

- With independent speed-regulatable motors used for driving the twomeasuring dispensers and the agitator of the mixer, the speeds of thesemotors can readily be adjusted to a feeding rate sufllcient forpermitting the material granules to be surface-coated, although thequantity of liquid is insuihcient for having the liquid soak so deeplyinto the particles as to crowd air out of a large portion of the airspaces within these particles. This liquid surface-coating on thematerial then acts like a lubricant in enabling the material to slidefreely through the hose and through the usual material passage of thespray gun, the discharge of which gun can then consist almost entirelyof material particles coated with little more than a film of the liquid.

In practice, the proportions of my apparatus and the feeding rates ofthe two metering dispensers are desirably adjusted so that the level 20of the material will remain below the discharge outlets of the liquidsprays S, so that the agitator continually rotates the material underthe row of sprays.

By thus distributing upon the material particles, such as granules ofcork, an amount of adhesive merely sufficient for insuring asurfacecoating of these granules, I not only avoid the use of anexcessive quantity of the adhesive but also can leave the greater partof the interior chambers in the cork filled with air so as to retain theheat-insulating and sound-deadening effect of this air. Moreover, bythus limiting the quantity of adhesive affixed to each granule of cork,I avoid a swelling of the cork granules which might otherwise causethese to jam the material passage of the gun and also of the hose 1-1when the operation of the gun is temporarily halted. Consequently, whenthe supply of compressed air is shut off at the end of each workingperiod, a detaching of the hose H from the mixer and from the gun willallow the residual contents of the latter to flow out through the hose,and both the mixer casing and the hose can thereafter be flushed outwith a suitable liquid.

By using sealed pressure tanks and a sealed mixer, as shown in Fig. 1, Ialso avoid a contamination of both the material and the liquid bymoisture or impurities in the air around the apparatus. Moreover, a gasother than air (as for example, carbon dioxide) can be used in place ofthe compressed air if the adhesive or other binder is such as would beaffected by air.

Owing to the decided increase in the readiness with which most particlesof porous material will slide through any duct or passage when theseparticles are film-coated with liquid, my apparatus also permits thespraying of larger particles than would otherwise be feasible with agiven spray gun. In practice, I desirably employ a spray gun which hasan axially straight material pas sage extending entirely through it,such as the one disclosed in my copending application #191179, filed May4, 1935 on a Spray gun for asphalt or the like. With such a gun, aspringopened switch It can readiiy be fastened to an exterior gun part,as shown in Fig. 3., with the movable circuit-closing member I! disposedin the path of a finger i8 fastened to the actuating handle I! of thegun.

However, many changes from the heretofore described construction andarrangement of my apparatus may obviously be made without departingeither from the spirit of my invention or from the appended claims. Forexample, the

needed adjustments in the relative rate of operation of thematerial-metering dispenser, the liquid-metering dispenser and theagitator of the mixer can be obtained with the use of a single motor, asshown in Fig. 2. In this figure, the motor 28 for driving the agitatorhas a shaft 29 carrying cone pulleys 2| and 22 connected by belts 23 and24 respectively to cone-pulleys associated with the material dispenser land the liquid dispenser 3.

Thus'connected, the speeds of the two dispensers can be variedindependently by shifting the corresponding belts in the manner forwhich tapering belt pulleys are commonly designed, and the rate at whichthe entire system operates can be varied (according to the nature of thematerial and liquid, and also according to the needed spraying capacity)by using a motor 28 which includes a variable speed reducing gearing.

So also, while Figs. 1 and 2 each show only a single spray gun, itshould be obvious without separate picturing that a plurality of suchguns could be connected to the same hose or other discharge duct, eachadditional gun having its circuit-closing switch connected in multiplewith the circuit wires shown at lllb in Fig. 1 as lead ing to the thereillustrated gun, as for example mediately spraying the coated granules,this apparatus could obviously be employed also for coating materialparticles with other liquids-as for example with a waterproofingliquid-and delivering these into a container instead of projecting themby means of a spray device.

I claim as my invention: v

1. An apparatus for supplying adhesive-coated and comminuted solidmaterial to a spray device, comprising a mixer casing sealed against theentry of atmospheric air and having its lower portion connected to thespray device; an agitator within the said casing; means also sealedagainst the entry of atmosphericair for feeding both material anda-liquid adhesive into the upper portion of the said casing, the saidmeans being adjustable to effect the said feeding at such relative ratesthat the fed adhesive suflices only for surface-coating the particles ofthe fed material; means driving the agitator; and means for supplying acompressed gas to the upper portion of the said mixer casing for forcingthe resulting adhesive-coated particles of material out of the saidcasing and into the spray device. 2. An apparatus as per claim 1,including means for adjusting the relative rates of the feeding of thematerial, the feeding of the binder, and the speed of the agitator.

3.An apparatus as per claim 1, including a material container and anadhesive container from which the material and the adhesive arerespectively fed to the mixer casing, and means for maintaining theinterior of the said two containers under the same gaseous pressure asthat of the mixer casing.

4. A system for supplying adhesive coated particles of solid material,comprising: a mixer, an

' agitator disposed in the mixer, a material-containing tank and anadhesive-containing tank both supported at higher elevation than themixer; means connected to the upper portions of the mixer and of both ofthe said tanks for maintaining the said upper portions under gaseouspressure; two ducts respectively leading from the bottom of the said twotanks to the upper portion of the mixer; two measuring dispensersoperatively disposed respectively in the said two ducts; an outlet ductconnected to the bottom of the mixer, and conjointly operable means fordriving the agitator and the two measuring dispensers; the said drivingmeans being adjustable to vary the relative speed of the agitator andthe dispensers, so as to vary the extent to which the said particles arecoated with adhesive while passing through the mixer.

5. A system as per claim 4, including a spray appliance connected to thesaid outlet duct, and in which the gaseous pressure in the two tanks andin the mixer affords sole means for forcing the material and adhesivethrough the outlet duct and into the spray appliance.

6. An apparatus for spraying adhesive-coated particles of material,comprising a spray appliance, a duct leading to the said appliance, amixer including a casing having its outlet connected to the said duct,and an agitator within the said casing; a material-containing tank andan adhesivecontaining tank both connected to the upper portion of themixing tank, two measuring dispensers respectively interposed betweenthe two tanks and the mixer; conjointly operable means for actuating theagitator and the two dispensers at predetermined relative rates, andcontrol means operatively interposed between the spray appliance and thesaid conjointly operable means for halting the actuation of the agitatorand the dispensers when the spray appliance is not being actuated.

7. A system as per claim 4, including means within the mixer fordischarging the adhesive supplied to the mixer casing in the form ofdownwardly directed sprays within the said mixer casing.

8. An apparatus for spraying adhesive-coated particles of material,comprising a spray appliance, a duct leading to the said appliance, amixer including a casing having its outlet connected to the said duct,and an agitator within the said casing; a material-containing tank andan adhesive-containing tank both connected to the upper portion of themixer casing, two measuring dispensers respectively interposed betweenthe two tanks and the mixer; conjointly operable means for actuating theagitator and the two dispensers at predetermined relative rates, andmeans for maintaining the upper portions of the two tanks and of thecasing of the mixer under a gaseous pressure sufllcient for forcing thesaid particles out of the mixer casing and through both the said ductand the spray appliance after these particles have been coated withadhesive while in the mixer casingl 9. An apparatus as per claim 8, inwhich the spraying appliance includes a manually movabledischarge-controlling means, and in which the said automatic haltingmeans comprise instrumentalities associated with the said manuallymovable means of the spray appliance for starting and halting of thesaid conjointly operable means in response respectively todischarge-opening and discharge-closing movements of the said manuallymovable means.

10. An apparatus for feeding comminuted material and a liquidrespectively from a material container and a liquid container into amixer which includes an agitator and thereafter through a pipe line to aspray-appliance, comprising means for maintaining the interior of bothcontainers and of the mixer under gaseous pressure; motor-driven meansfor operating the agitator and for measuring suitably proportionedquantities of material and liquid respectively from the said containersinto the mixer; jointly controllable circuits leading to the saidmotor-driven means; manually startable means for initially closing thesaid circuits and for automatically opening the said circuits after apredetermined lapse of time; and means mounted upon and responsive tothe actuation. of the spray appliance for closing the said circuits onlyduring each actuation of the spray appliance.

11. An apparatus for feeding comminuted material and a liquidrespectively from a material container and a liquid container into thecasing of a mixer which houses an agitator and thereafter through a pipeline to a spray-appliance, comprising means for maintaining the interiorof both containers and of the mixer under gaseous pressure; motor-drivenmeans for operating the agitator and for measuring suitably proportionedquantities of material and liquid respectively from the said containersinto the mixer; jointly controllable circuits leading to the saidmotor-driven means; and two switches disposed for independentlycontrolling the supply of current to the said circuits, one switch beinga manually startable time switch arranged for shutting off the supply ofcurrent after a predetermined time interval, and the other switch beingassociated with the spray appliance and arranged for maintaining asupply of current only during the periods of operation of the sprayappliance.

12. An apparatus for surface-coating particles of material with aliquid, comprising a mixer casing having a discharge outlet in its lowerportion; an agitator within the mixer casing; a material containerconnected to the upper portion of the mixer casing; a liquid container;a liquid pipe leading from the liquid container into the upper portionof the mixer casing and presenting discharge outlets for spraying theliquid downwardly within the mixer casing in jets discharged at higherelevation than the top of the agitator; two metering devicesrespectively controlling the discharge of material and of liquid fromthe'said two containers; coniointly operable means for actuating theagitator and the two metering devices, and means associated with thesaid conjointly operable means for adjusting the relative rate ofoperation of the agitator and the two metering devices.

13. The method of supplying adhesive-coated particles of solid materialto a duct leading ifromv a mixer to a spray device which comprises thecontinuous feeding of such material particles and of a liquid adhesiveinto the mixer under the infiuence of gaseous pressure suil'icient forexpelling the resulting mixture from the mixer through the said duct andthrough the spray device, and simultaneously therewith agitating thematerial particles and the adhesive within the mixer, at such relativerates of the said feeding that the said particles will only besurface-coated with the adhesive liquid while passing through the mixer.

14. The method of coating particles of solid material with a liquidadhesive and forcing the resulting adhesive-coated particles intoa'duct, which comprises the simultaneous downward feeding of suchmaterial and adhesive into a mixer sealed against the outer air andconnected to the said duct while maintaining the upper portion of theinterior of the mixer under gaseous pressure, and the agitating of thematerial and adhesive within the mixer, the said feeding and agitationbeing at such relatively proportioned rates that the particles ofmaterial are only surface-coated when forced from the mixer into thesaid duct by the said gaseous pressure.

15. The method of coating particles of solid material with a liquidadhesive which comprises as simultaneous steps the feeding of the saidparticles into a mixer sealed against the outer air and having a bottomoutlet, the spraying of the adhesive downwardly within the upper portionof the mixer, the maintaining of a gaseous pressure pressure.

SVEND BRAMSEN.

